Faulty fridge

I bought a fridge ,in august when it came within a day it was not working nicely ,then few weeks later its not getting cold ,i been calling an still nothing i was promise that by saturday this will sorted an still no one even came home or even called too say anything ,my food is gone off ,what do i do now ,am so upset an i cnt believe anything they say any more ,i have a kid at home ,because of this even the food i just bought are gone off,what ****ing me off more is that i paid CASH for it